I want to add a SIP header to the messages going back to the phone. For example :
SIP Phone 1 calls Asterisk ( 123 )
Asterisk calls SIP Phone 2 ( 123,1,Dial(SIP/SIPPhone2|90)
If I use SIPAddHeader(X-Some-Header: Value ), it will add it to the SIP INVITE going to SIPPhone2. How can I add headers to other packets? Such as a 183 Session Progress or a 200 OK? I need to send special info back in the SIP headers to the origin of the call.